Stock crowder



Dec. 13, 1960 w. P. CARPER 2,964,003

STOCK CROWDER Filed Aug. 29, 1956 VIII/1'" 120 7 INVENTOR. 1259 WILLIAM P. CARPER I BY W4 W1 M4! W ATTOR N EYS 2,964,003 Patented Dec. 13, 1060 United States Patent-'fiice STOCK CROWDER William P. Carper, Trotwood, Ohio (1137 Welfare Ave., Dayton 29, Ohio) Filed Aug. 29, 1956, Ser. No. 606,925

4 Claims. (Cl. 113-49) This invention relates to metal working presses and more particularly to a stock crowder or pusher adapted to position thestock prior to the entry of pilots and punches or other metal forming dies.

The crowder moves the stock against the back gauge, or other limiting means such as another crowder at the other side of the die set. It can be used to push directly against the stock, or against a plunger in the stripper rail. When the die is opened by the action of the press, the stock is left free to be advanced to the next working position by the operator or by an automatic feed.

It is a primary object of this invention to provide a stock crowder of the above type which is adapted to be made in large quantities of uniform size and shape so they may be purchased by users of metal presses at reasonable cost, and which may be adapted to presses of varying sizes with a minimum of shop work by the user.

Another object of the invention is to provide a stock crowder which is essentially a self-contained unit capable of direct mounting on the die shoe of a die set without machining or like work operations by the user.

An additional object of the invention is to provide a crowder which can be made to lift the successive parts from the dies after the forming operations thereon so they may be more readily removed from the press or advanced to another operation in the press.

It is also an object of this invention to provide a stock crowder which may be attached to the die set with great accuracy and with a minimum of work.

Additional objects and advantage of the invention will be apparent from the following description, the accompanying drawing and the appended claims.

In the drawing- Fig. l is a vertical view, partly in elevation and partly in section, showing a crowder attached to a typical die set;

Fig. 2 is an enlarged top plan view of the crowder before it has been attached to a die set;

Fig. 3 is a section on the line 3-3 of Fig. 2;

Fig. 4 is a vertical section taken along the line 4-4 of Fig. 2;

Fig. 5 is an enlarged view of a portion of Fig. 1;

Fig. 6 is a view somewhat similar to Fig. 1 showing the crowder attached to another typical die set;

Fig. 7 is a view somewhat similar to Figs. 1 and 6 showing the use of two crowders on each side of the stock, and also showing how the crowder may be used to lift the finished parts from the stationary die; and

Fig. 8 is a fragmentary section similar to Fig. 1 showing another form of the crowder of the invention.

Referring to the drawing, which illustrates preferred embodiments of the invention, a typical die set with which this invention may be used is illustrated in Fig. 1 as having a movable die shoe 10 which carries and moves a movable die 11 into engagement with a stationary die 12 carried or held by the stationary shoe or base 13. A stripper rail 14 has a flange 15 which forms one guide for the work stock 16 which is being fed perpendicularly effecting positioning of the stock and comprising a plate slotted at 18 to receive a retaining guide pin 19 set in the stripper rail 14.

The stock crowder or pusher of the invention is generally designated by the numeral 20 and it is shown in Fig. l as operating to push against the plunger 17, which pushes against the stock 16 and correctly positions the stock against the edge of the flange 15 prior to the time that the die 11 punches or otherwise acts upon the stock 16. However, the crowder may move directly against the stock, instead of through the medium of a plunger, in the manner later described in connection with Figs. 6 and 7.

The crowder 20 includes a block 22 of metal which is advantageously of rectangular shape, and which supports therein a lever 25 which is the main operating member of the unit. This lever is generally right angled, and it includes-a generally horizontally extending arm 26 and a generally vertical depending arm 27. The lower end of arm 27 has a beveled face 28 which forms a cam for engagement with the work as described hereinafter.

A substantially horizontal rectangular groove 30 is cut in the top of the block 22, and a similar groove 31 is cut vertically through one side of the block to form a continuation of the groove 30 while leaving a saddle-like portion 33 connecting the resulting two parts of the block. The lever 25 is received within the grooves 30 and 31, and the sides of these grooves are preferably parallel faced for smooth guiding relation with the similarly parallel faced sides of the levers 25. As shown, the horizontal arm 26 of the lever overhangs the saddle portion 33, and the lever is pivoted within block 22 by a pin 35 extending through the upper corner of the block at approximately the point of intersection of the grooves 30 and 31, and similarly extending through the lever 25 at the point of its intersection of its arms 26 and 27.

In use, the crowder 20 is mounted on the die shoe 10 with the flat upper surface 40 of block 22 parallel with the lower or advancing face 41 of the die shoe. The block 22 may be mounted directly on the die shoe, or it may be spaced therebelow by means of a parallel faced spacer as shown at 42. By the use of the single spacer 42 of the correct vertical dimension, or a plurality of such spacers stacked upon each other, the block 22 can be correctly spaced below the shoe 10 to adapt the crowder to use with dies of difierent shut heights.

thus to urge the depending lever arm 27 laterally to the maximum extent permissible by engagement between the pad portion 45 of lever arm 26 and the saddle portion 33 of the block 22. The spring 44 seats at its lower end in a counterbore 46 in the upper surface of lever arm 26, and the upper end of the spring seats in a similar counterbore 47 in the lower face 41 of the die shoe. If a spacer 42 is used, it is provided with a through bore 48 for receiving spring 44 therethrough.

As noted, the pivoting movements of the lever 25 in block 22 are guided by the side faces of the lever and the slots 30 and 31, and special provision is accordingly made for simple and effective lubricating of these surfaces. A bore 50 is provided completely through both sides of block 22 and coincides with a bore 51 through 53. In addition, grooves 55 and 56 are provided on both 1 2 sides of the lever 25 which communicate directly with.

the bore 51 and extend around the pivot of pin 35 and partway down the depending lever arm 27 Thus when lubricant is introduced under pressure to the fitting 52, it will efiectively lubricate both sides of the lever almost instantaneously. The fitting 52 and plug 53 may be interchanged depending upon the installation conditions of the unit.

Special provision is made in accordance with the invention for simply and easily establishing the correct accurately positionedmounting of the crowder unit 20 on the die shoe 10. Referring particularly to Fig. 2, the block 22 is provided at one pair of corners with blind tapped bores 60 and 61, and smooth bores 62 and 63 are provided in the other pair of corners. A pair of holes are bored through the die shoe for receiving through bolts 65 (Fig. 6) which are threaded into the bores 60 and 61 for supporting the block in approximately the correct position- The block is then adjusted accurately, through the clearance of the bolts 65 in the die shoe, to the proper accurately aligned relation with the die, and then holes are bored up into the die shoe through the bores 62 and 63 into which dowels 66 are driven to provide a firm interconnection between the block and the die shoe which will resist angular displacement of the crowder.

Provision is also made in accordance with the invention for accurately establishing the proper location for the counterbore 47 which receives the upper end of the spring 44. Referring particularly to Fig. 4, a bore 70 of small diameter extends centrally through the saddle portion 33 in alignment with a somewhat larger bore 71 extending through the lever arm 26 from the bottom of counterbore 45. While the block is mounted temporarily in position and before the dowels 66 are inserted, the bores 70 and 71 are utilized to receive a suitable instrument for marking the proper location of the center for the counterbore 47, and the latter is formed after the block has been temporarily removed. The same procedure may be followed if a spacer 42 is used, with all of the several bores passing through this spacer.

During the above installation operations, the lever 25 is preferably held in intermediate position corresponding with reasonable accuracy with the position it should occupy when it is performing its pushing or crowding operation. For this purpose, a bore 75 (Fig. 6) is provided in one side of the block 22 which is adapted to register with a tapped bore 77 in the side of lever arm 27 for. receiving a temporary locking screw (not shown). This screw is removed while the machine is in operation, and Fig. 1 illustrates how the lever arm 27 engages and forces the plunger '17 towards the work as the die shoe descends. The beveled face 28 engages plunger 17 first, and after the plunger has moved to the maximum permissible extent, it will have a cooperative cam action with the face 28 to force the lever in clockwise direction against spring 44 while the spring in turn maintains the crowding action of the lever throughout the remainder of the stroke of the press.

In manufacture of the crowder of the invention in quantity, the arm 27 preferably is madelonger than indicated in any of the figures, and is left in soft condition, so that it can be cut to a proper length and be given the desired shape at the bottom, as indicated in the various figures. For example, the beveled face 28' and the end of lever arm 27 may be cut by the manufacturer, on order from the user, or they may be cut by the user, and the lever is hardened after such cutting. When used with certain presses, the original length of the arm 27 may be sufiicient so no spacers 42 are necessary, and any slight variation in the shut height of the press may be compensated by the proper cutting at 28.

In Fig. 6, the dies are shown as performing a forming operation instead of a piercing operation. The die shoe 10', movable die 11', stationary die 12, base 13', crowder 20 and spacer or spacers 42" otherwise all correspond in construction and operation withthe similarly numbered parts previously described in connection with Figs. 1

through 5, but the plunger 17 has been omitted, and the arm 27 bears directly against the stock 16. The dotted lines 27a indicate the position of arm 27 when it has correctly positioned the stock 16' before the forming operation. As the forming proceeds, the arm is moved to the right by the action of the spring 44, which causes the arm 27 to follow any movement of the edge of the stock 16. No indication has been made of the spring 44, or other details, which are understood to be present in this embodiment. Since this die set of Fig. 6 does not have a stripper rail, 2 gauge 15' on die 12 has been indicated as guiding the opposite edge of the stock 16 as it is fed through the press, and the part 14' is an ejector.

Fig. 7 shows an arrangement generally similar to that of Fig. 6 except that a pair of crowder units are used on opposite sides of the stationary die, and not only do they serve cooperatively to maintain the stock in position, but also they are of special construction such that they serve to lift the work out of the die block during the upward stroke of the press. The die shoe 110, die 111, and other similarly identified parts in Fig. 7 correspond to the similarly numbered parts in Fig. 6 and therefore require no further description. The dies 111 and 112 are shown as having a cooperative forming action requiring the work to be lifted out of the die 112 after the work stroke is completed, and the part 114 is therefore a spring part of conventional construction. Therefore, the lever arms 127 are each shown as having a hook portion 129 formed thereon above the beveled face 128.

In the operation of the apparatus of Fig. 7, the two crowder units operate generally as described in connection with Fig. l, and during the first part of the downward stroke of the press, their beveled faces 128 engage and center the stock 116 until the moving die 111 has entered the stationary die 1:12. This action will automatically retain the stock properly centered, and thereafter the lever arms 127 continue downwardly a suflicient distance for their hook portions 129 to pass below the side edges of the work. Therefore, when the press carries out the upward part of its stroke, these hook portions 129 will engage the work and lift it out of the lower die a sufiicient distance for handling manually or by other suitable ejecting means.

The crowder unit shown in Fig. 8 is entirely selfcontained in that the spring which provides the desired biasing force on the lever operates between the horizontal lever arm and the supporting block. As shown, this unit includes a block 130 which is of essentially the same construction as the block 22 except that its saddle-like portion 131 is provided with a counterbore 132 in its upper surface for receiving the lower end of the spring 133. The lever 135 is similar to the lever 25 and includes a horizontally extending arm 136 and a depending arm 137, and it is similarly mounted in'the block 130 by the pivot pin 138.

The lever arm 136 overhangs the portion 131 of the block .130, and it is provided in its under surface with a counterbore 140 which receives the upper end of the spring 133'. The biasing force of the spring therefore urges arm 136 upwardly, which is the opposite of the arrangement shown in the other views, and accordingly this unit is mounted in use in the opposite way from the crowder units shown in the other views, namely with the inner face of the depending lever arm-137 facing the work, which is represented in Fig. 8 by the same parts as shown in Figs. 1 and 5. The inner edge of lever arm 137 is accordingly provided with a hardened and ground face 141 for engaging the plunger 17, but otherwise the operation of this unit is the same as previously described.

The block 130 may be identical in construction with the block 22 except for the spring seat 132, and it is therefore'mounted for use by the same means described in connection with Fig. 2. As shown in Fig. 8, a spacer 42 may be used, and the end of the lever arm 136 is provided on its upper surface with a raised boss 142 to serve as a stop by engagement with the under surface of the spacer 42 or the die shoe if the spacer is not used. The set screw 145 in the tapped bore 146 extending through the lever arm 137 corresponds in function to the bore 75 and associated locking screw previously described in connection with Fig. 6, and the screw 145 is removed before the device is set in operation. It will also be apparent that the lever arm 137 may be provided with the modified construction previously described in connection with Fig. 7, for the same purpose.

While the forms of apparatus herein described constitute preferred embodiments of the invention, it is to be understood that the invention is not limited to these precise forms of apparatus, and that changes may be made therein without departing from the scope of the invention which is defined in the appended claims.

What is claimed is:

l. A device of the character described in combination with a fiat horizontal advancing face of a die shoe to position the stock with relation to said shoe, comprising a body member having a smooth upper surface facing said shoe face and having also generally vertical front and back faces, said body member having a generally horizontal groove in said upper surface and a generally vertical groove in one of said generally vertical faces thereof which intersects with said horizontal groove to provide said member with two side portions connected by a saddle-like middle portion, a generally right angled lever received in said grooves in guided relation with the side surfaces thereof and with one arm of said lever lying in said horizontal groove in overhanging relation with said saddle portion and the other arm of said lever depending through said vertical groove, a pin received in said lever and said side portions of said body member to form a horizontal pivot for said lever, a spring carried by said body member and said lever for biasing said lever in the direction to cause said depending arm to move in the direction from said back face toward said front face, and means extending vertically through said side portions of said body member and securing the top surface of said member in predetermined fixed position on said die shoe surface with said front face toward the stock for biased crowding engagement of said depending lever arm with the stock during downward movement thereof with said die shoe.

2. A device of the character described in combination with a flat horizontal advancing face of a die shoe to position the stock with relation to said shoe, comprising a block of generally rectangular proportions having a smooth upper surface facing with said shoe face and having also generally vertical front and back faces, said block having a generally horizontal groove in said upper surface and a generally vertical groove in one of said generally vertical faces thereof which intersects with said horizontal groove to provide said block with two side portions connected by a saddle-like middle portion, a generally right angled lever received in said grooves in guided relation with the side surfaces thereof and with one arm of said lever lying in said horizontal groove in overhanging relation with said saddle portion and the other arm of said lever depending through said vertical groove, a pin received in said lever and said side portions of said body member to form a horizontal pivot for said lever, a spring carried by said block and said lever for biasing said lever in the direction to cause said depending arm to move in the direction from said back face toward said front face, and means extending vertically through said side portions of said body member and securing the top surface of said member in predetermined fixed position on said die shoe surface with said front face toward the stock for biased crowding engagement of said depending lever arm with the stock during downward movement thereof with said die shoe, said securing means including a dowel hole and a screw hole extending vertically through each of said side portions of said block.

3. A device as defined in claim 1 wherein said depending lever arm includes a beveled portion on the front of the lower end thereof for camming engagement with the edge of the stock during said downward movement of said device with said die shoe.

4. A device as defined in claim 3 wherein the front edge of said depending lever arm is offset above and with relation to said beveled portion thereof to form a hook for lifting the stock during upward movement thereof with said die shoe.

References Cited in the file of this patent UNITED STATES PATENTS 315,749 Donahue et al Apr. 14, 1885 1,415,838 Griffiths May 9, 1922 2,067,943 Norquist Jan. 19, 1937 2,369,551 Feiler Feb. 13, 1945 2,826,161 Palmer Mar. 11, 1958 

